/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the copyright holder nor the names of its contributors 
 * may be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.system.util;

import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Base64;

/**
 * Utility class for encoding and decoding operations.
 *
 * @author Lars Helge Overland
 */
public class CodecUtils {
  private static final String ILLEGAL_FILENAME_CHARS_REGEX = "[/\\?%*:|\"'<>.]";

  /**
   * Encodes the given string by removing chars which are illegal on most file systems.
   *
   * @param string the string to encode.
   * @return an encoded filename string.
   */
  public static String filenameEncode(String string) {
    if (string != null) {
      string = string.replaceAll(ILLEGAL_FILENAME_CHARS_REGEX, "");

      if (string.length() > 255) {
        string = string.substring(0, 255);
      }
    }

    return string;
  }

  /**
   * Returns a basic authentication string which is generated by prepending "Basic " and
   * base64-encoding username:password.
   *
   * @param username the username to use for authentication.
   * @param password the password to use for authentication.
   * @return the encoded string.
   */
  public static String getBasicAuthString(String username, String password) {
    String string = String.format("%s:%s", username, password);
    return "Basic " + Base64.getEncoder().encodeToString(string.getBytes());
  }

  /**
   * Encode the given string using URLEncoder and UTF-8 scheme
   *
   * @param string
   * @return encoded string
   */
  public static String utf8UrlEncode(String string) {
    try {
      return URLEncoder.encode(string, StandardCharsets.UTF_8.name());
    } catch (UnsupportedEncodingException e) {
      throw new RuntimeException(e);
    }
  }
}
